Building A 935 K4 At Madlane Japan – Speedhunters


At just 27 years of age, Kazuki-san has built a number of slammed, modified and restored supercars, and you can read about some of those here. They’re impressive for sure, but now Kazuki-san is really stepping up his game by taking on the incredible challenge of recreating one of the greatest Porsche track cars of all time.


The Kremer Racing 935 K4 was the final iteration of the Kremer brothers-built 935s that dominated a number of races and series in the late 1970s and early ’80s including the IMSA GT championship, DRM, Sebring and the Nürburgring 1,000km. 

Racing legend John Fitzpatrick, who owned and drove the first Kremer 935 K4, confirms: “The K4 was a sensational car, the fastest 935 ever, and still is.” 


With its sleek custom silhouette built around the remnants of a factory 930 Turbo roof, the Kremer 935 K4 had immense presence on the track. Kazuki-san is now bringing that magic to the streets of Japan.

The base car for Kazuki-san’s build is a 964 Carrera 2, although, just like the Kremer 935 K4, there’s not much of the original car left, especially at the rear. The 964 chassis has been completely replaced from the rear door sills back with a tube frame hand built by Kazuki-san.   


From an engineering standpoint, I was intrigued at how Kazuki-san had mapped out the frame and especially how he has calculated the position of the rear suspension setup. He’s used the hubs and control arms from a 993, but with a pushrod suspension.

What you see are just motorbike shocks for the fabrication process and to move the car around. He’s having custom billet case and external tank units made for actual use.  


To create something tangible from nothing but an idea takes time, knowledge, resources and a decent-sized budget. Luckily for us, Kazuki-san can tick all those boxes.


Knowledge is probably the most important element of this build. Most of the car’s dimensions and form have been created using photos and even plastic models of the Kremer 935 K4. There are no online car forums to follow for build tips, and likewise there are no blueprints or spare parts to copy.

There is, however, a master Porsche mechanic living in Kobe, a few hours from Madlane HQ, and he has been guiding Kazuki-san with many of the technical details. 


It would be madness to go through all this and not have the K4 drive like a proper race car, right? Absolutely, and that’s why Kazuki-san has chosen a 3.6L 964 flat-six, bored out to 3.8L. To make big power, Kazuki-san will use twin KKK turbos with 935 wastegates and manifolds from Reid Washbon Racing Exhausts in California.

Just like in the original Kremer 935 K4, the gearbox is upside down which makes the drive shafts parallel and reduces wear on the universal joints. 


As I read more about the K4 and look through my photos of Kazuki-san’s build, my heart is racing with excitement. This isn’t just going to be show car that looks like a race car – this is going to be a proper K4 replica with the guts to match. 


While much of the build is a piecing together road car parts, custom panels and fabricating the tube frame from scratch, there is something very special that brings a heavy dose of authenticity to this build, matched by no other.  


Resting in a dusty corner of the workshop sits a rear cowl from the John Fitzpatrick-owned and developed Kremer 935 K4.


This is a cowl which covered the engine that pushed the car to victory countless times. How cool is that?


There’s obviously much more to cover with this build, but Kazuki-san has asked that it’s kept secret until the car is finished. For now, let’s just be happy that another 935 K4 is being brought into existence.

Toby Thyer
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